Turn-ons: game theory, combinatorics, probability, progressive rock.
Turn-offs: that feeling when someone rubs paper on chalkboard.

Time complexity of number of solutions to equation of varying size, with varying upper-bound range restrictions
Zeilberger quick how-to: https://math.stackexchange.com/a/4322239
How to ask a good question advice: https://math.meta.stackexchange.com/a/34067
Independence vs equally likely outcomes: (1) (2) (3) (4) (5) (6) (7)